The 12" PVC Class 125 Cap (Slip) is a large-diameter thermoplastic end cap designed to permanently close the open end of a 12-inch PVC pipe. The single slip socket accepts standard Class 125 PVC pipe and installs via solvent cement, creating a sealed, pressure-tight termination that is structurally integral with the pipe run and requires no hardware, gaskets, or mechanical fasteners.
Pipe caps serve a straightforward but essential function in any piping system: cleanly and permanently terminating a run at its endpoint. At the 12-inch scale, caps appear most frequently in municipal drainage and stormwater systems, large commercial drain mains, and civil infrastructure where a mainline, stub-out, or future-connection point must be sealed against infiltration, debris, or backflow until the system is commissioned or extended. A solvent-welded cap at this size provides a termination that is as structurally sound as any other joint in the system — there is no weak point, no potential for the cap to back off under pressure or thermal movement, and no ongoing maintenance requirement once installed.
Class 125 PVC fittings are dimensioned to the cast iron pipe fitting pattern, making this cap the correct choice when working within a Class 125 system or when replacing a cast iron end cap in existing large-diameter drainage infrastructure. This dimensional standard differs from Schedule 40 PVC, and the two are not interchangeable at the fitting level in applications where cast iron pattern geometry is specified. Manufactured to ASTM D2466 standards and dimensioned to the cast iron pipe fitting pattern for compatibility with mating Class 125 components.
Specifications:
| Attribute |
Detail |
| Part Number |
C647-120 |
| Material |
PVC (Polyvinyl Chloride) |
| Classification |
Class 125 (Cast Iron Pattern) |
| Size |
12 Inch |
| End Connection |
Slip (Socket) |
| Fitting Type |
Cap |
| Standard |
ASTM D2466 |
| Dimensions |
Cast Iron Pipe Fitting Pattern |
| Color |
White |
| Max Pressure (Water @ 73°F) |
125 PSI |
| Temperature Range |
Up to 140°F (60°C) |
| Compatible Pipe |
Class 125 / Cast Iron Pattern PVC Pipe |
| Joint Method |
Solvent Cement Weld |
Industries & Applications:
- Municipal Drainage & Stormwater — Used to terminate large-diameter stormwater mains, drainage stub-outs, and future tie-in points in underground infrastructure where a permanent, infiltration-proof seal is required until the system is extended or connected
- Large Commercial Building Drainage — Applied at the terminal ends of below-grade drain mains in large commercial, institutional, and industrial buildings where 12" gravity drain runs require a clean, code-compliant termination
- Civil & Site Utilities — Specified on site utility plans to cap underground drainage runs, stub-outs for future phases, and temporary line terminations during phased construction on large commercial and institutional developments
- Industrial Discharge & Process Drainage — Used to seal the terminal end of large-bore industrial drain headers or discharge lines during system commissioning, equipment changeover, or phased facility buildouts
- Cast Iron System Replacement & Retrofit — A direct retrofit end cap for aging cast iron drainage systems being upgraded to PVC; Class 125 dimensional compatibility eliminates the need for transition fittings at the termination point
- Water & Wastewater Treatment Facilities — Incorporated at the ends of gravity drainage headers, effluent conveyance lines, and process drain stubs within treatment plant infrastructure where large-diameter PVC terminations are required
